Hydroxy-benzanthrones and process of making same



I The same compounds Patented 1.... 11, 1927.

um'rao STATES PATENT OFFICE.

KARL scnmmacnnn,

1mm. zArm, AND KARL wrLxE, AND ram. ocnwn'r, or BAD-SODEN, GERMANY, ASSIGNOBS,

OF HOCHST-ON-THE-MAIN,-

BY HESNE ASSIGN- MENTS, TO GRASSELLI DYESTUFF CQRPOBATICN, OF NEW YORK, N. Y., A CORPORA:

TION or DELAWARE.

HYDBOXY-IBENZAHTHBONES AND PROCESS OF MAKING SAME.

No Drawing. Application filed April 28,

We have found that new hydroxybenzanthrones can be obtained by nitrating and saponifying an acyl compound of the aminobenzanthrones derived from benzan 5 thrones by nitration and reduction-diazotizing the nitroamino compounds and treating with agents eliminating amino groups the diazo oxides formed from the diazo compounds by the action of water:

are also obtained by heating 6-methoxy 1 benzoylnaphthalines together with aluminium chloride. The new hydroxybenzanthrones have the following constitution and are therefore to be designated as Bz-2- hydroxybenzanthrones.

In these hydroxyb'enzanthrones the hydrogen atom of the hydroxyl group may be easily replaced by a radical if the compound is treated with halogen alkyls or any other alkylating agents. This fact could not be foreseen, because for instance according to the statements by Perkin (see Journal of the Chemical Societ 121, page 476) the isomeric hydroxybenzantlirone prepared from ochydroxyanthraquinone could not be converted into the corresponding methyl ether. new products are intended to be used as in- .termediate products for making dyestuffs.

0 The following examples illustrate our invention: 1. 50 parts of aminobenzanthrone having a melting point of about 240 C. and being soluble in concentrated sulfuric acid with at a ye owish brown 7 color and a brownish The 1924, Serial No. 709,679, and in Germany June 25, 1923.

green fluorescence (obtained by reducing the nitrobenzanthrone having the formula obtainable according to Example 1 of patent of addition 6435 to French Patent 3422531) are introduced into 500 parts of nitroben- 2 hours. After having cooled the mixture to 5, 40 parts. of nitric acid (specific gravity 1, 5) are added and the whole is heated for 2 hours to C. The mass, when 0001, is

filtered oil? and washed with spirit and dried 66 parts of the yellow nitroaceto compound thus obtained are introduced in the form 70 of a fine owder ,mto 1,200 parts of sulphuric acid 70%) and heated for 2 hours to 90. The whole is then cooled down to 10 C. and diazotised at the calculated quantity of nitrosyl sulphuric acid. During this operation the crystalline magma, which is at first dark greenish-blue, changes into a brownish-yellow solution. After 2 hours have passed, the solution is poured on ice, diluted with about 10,000

arts of water and stirred for 24 hours. l Juring this o eration the orange-yellow diazo compoun turns into an olive-coloured, voluminous diazo-oxide, which is separated from the liquid by filtration and then washed out with water. The filtered mass is then triturated with a small quantity of water so as to become a v is slowly added while cooling with ice an kal ne solution of 70 parts of stannous this temperature with fine paste and there chloride and 200 parts of caustic potash in 1000 parts of water, whereupon the whole is stirred for 5 hours. After havingdiluted the mixture with 10,000 parts of water, it I5 is heated to boiling, filtered and the filtrate is precipitated, while hot, by means of hydrochloric acid. .After having filtered-and washed with water and dried, the hydroxybenzanthrone is obtained as a light yellow powder which dissolves in concentrated sulphuric acid with a yellowish-red colour and a brown fluorescence. In dilute alkalies it is soluble to a brownish-red solution and on addition of concentrated caustic soda solution the alkali salts separate as red precipitates. The product is difiicultly soluble in the usual organic solvents, and more readily soluble in hot nitrobenzene. Its melting point lies above 280 C. When heat- 30 edwith aceticanhydride and it yields an acetyl compound melting at 201. When fused with alcoholic potash, it furnishes a dyestufl' which dyes cotton from a blue hydrosulphite vat olive-green unfast tints.

2. 10 parts of the benzanthrone obtained according to Example 1 are shaken in an aqueous, akaline solution with dimethylsul- NE; NH. co

Bz-l-ainino-benzanthtono in which X designates hydrogen or an alkyl group.

7p 2. Process of producingBz-2-hydroxybenasodium acetate,

Oxy-diazo-anhydrld the oxydiazoanhyd phate until the light creases no longer. This precipitate is then filtered off and washed. When dry, it forms a light ellow powder, which is insoluble in water, diluted acids and alkalies but soluble in concentrated sulphuric acid-with a yellowish-red colour and a slight fluorescence. In organic solvents, the methoxybenzanthrone is rather easily soluble with a yellow,to brown colour. The diluted alcoholic solution shows a strong green fluorescence. After re-precipitation from benzene, brownish-yellow crystals are obtained melting at I'll-173 C. When fused with alcoholic potash it furnishes a dyestuif whiclndyes cotton from a bluish-violet hydrosulphite vat bluish green fast tints.

3. When treating the hydroxybenzanthrone prepared according to Example 1 with ethyl-iodide and alkali in an alcoholicaqueous solution, the corresponding ethyl other is obtained as a yellow product which very much resembles the methyl-ether in regard to its properties. After recrystallization it melts at 169170.

The mechanism formation of Bz-2-hydroxy-benzanthrone is indicated by the following equations:

NH.GO .CH:

Bz-2-Hydroxy-bonzunthrone.

anthrone com -nitrobenzanthrone to Bz-l-anlinobenzanthrone, acylating the obtained product, nitrating the Bzl-acylaminobenzanthroue,saponifyiug the nitro-Bz-1-acylamino benzanthrone, diazotising the nitro-Bz-lamino compound,- treating with water and substituting hydrogen for the nitrogen in ride.

In testimony whereof, we' afiix our signatures.

' KARL SOHIRMACHER.

KARL' ZAHN. KARL WILKE.

PAUL OCHWAT,

-yellow precipitate inof the reactions in the 

